Thomas Vermaelen completed his £15 million switch from Arsenal to Barcelona on the weekend, but when the Belgian international will be able to make his debut for his new club remains to be seen.

Just days after passing his medical, the La Liga side has revealed that a thigh injury sustained during the World Cup will keep the defender out for an ‘indefinite period’, with the club to determine when he will return to full training following further treatment.

Vermaelen’s departure from Arsenal was met with mixed reaction from fans, but this latest development leads one to wonder whether Arsene Wenger has dodged a bullet in offloading his former captain this summer.

Arriving from Ajax in 2009 for around £10 million, the centre-back became an integral part of the lineup during his first four seasons at the Emirates but, even then, his fitness record was never the best.

An Achilles issue saw Vermaelen make just five appearances in the whole of 2010-11, while further treatment on the problem the following September saw him miss six weeks of the 2011-12 campaign.

He would fare somewhat better in 2012-13 in his first full campaign as skipper, missing just six matches, but a stress fracture in his back would rule him out for the start of 2013-14, before mid-season knee trouble sidelined him for another 11 games.

No longer an automatic starter at Arsenal, Vermaelen’s obvious decline in fitness saw Wenger deem him expendable in North London and, despite his past reputation as one of the Premier League’s top defenders, there are clear signs to suggest that the best form of career is behind him.

Set to turn 29 in November, that didn’t prevent Louis van Gaal from attempting to bring the 47-times capped international to Manchester United but, much like when Wenger sold Alex Song to Barca in August 2012 for the same fee, this could well turn out to be another successful piece of business for the Frenchman.

Even if Vermaelen can conquer his recent fitness issues to go on to impress with the Catalan giants, with an already solid centre-back pairing of Laurent Koscielny and Per Mertesacker, it’s hard to scoff at the £15 million received for a potential backup.

As much as supporters don’t like to see the depth of the squad weakened or a clear fan favourite leave, Wenger’s decision could just prove to be the best thing for the long-term.

Freddie Shires

Freddie is a freelance sports writer, having recently completed an MA in Sports Journalism at St. Mary’s University, Twickenham. With an especially keen interest in all things American sports-related, he has written extensively about the NFL, MLS and the U.S. national team for various sites.